ACS Chemistry for Life

The race to bring biofuels to the pump
Chemical & Engineering News

C&EN Senior Correspondent Stephen Ritter notes that scientists have largely met the technical challenges of developing biofuels – fuels made from renewable biological resources – to supplement and eventually replace gasoline and diesel fuel. Starting points for biofuels include sugars, starches, vegetable oils, recycled paper, and other biomass. But the technological fog of choosing the appropriate resources for conversion obscures the road to the finish line. One major problem, for example, involves the logistics of biomass availability, transport, and storage. To be commercially viable, biomass fuel factories will need up to 30 million pounds of biomass per day. Fermentation facilities, which convert sugar to ethanol, would need about 10 million pounds. To win, companies must develop long-term reliable feedstock supplies and find partners to buy and market their fuel. The benefits include energy security by eliminating dependence on imported oil and a reduction in the carbon dioxide emissions that contribute to global warming.

New high-performance lithium-ion battery “top candidate” for electric cars
Journal of the American Chemical Society

Bruno Scrosati, Yang-Kook Sun, and colleagues are reporting development of an advanced lithium-ion battery that is ideal for powering the electric vehicles now making their way into dealer showrooms. The new battery can store large amounts of energy in a small space and has a high rate capacity, meaning it can provide current even in extreme temperatures. A typical hybrid car can only go short distances on electricity alone, and they hold less charge in very hot or very cold temperatures. The scientists developed a high-capacity, nanostructured, tin-carbon anode, or positive electrode, and a high-voltage, lithium-ion cathode, the negative electrode. When the two parts are put together, the result is a high-performance battery with a high energy density and rate capacity.

New guidelines may make it easier to share information on “going green”
Chemical & Engineering News

C&EN Senior Correspondent Stephen Ritter notes that chemical companies are eager to produce greener products, but there are no standardized criteria for determining whether starting materials and chemical processes are environmentally friendly. Many green standards already exist, but they are usually issued by companies themselves, industry trade groups, or environment-focused nongovernmental organizations. The standards, however, tend to focus on only one or two product attributes, such as content of volatile organic compounds or percent of recycled content, the article notes. The American Chemical Society’s Green Chemistry Institute (GCI) is spearheading an effort to create the “Greener Chemical Products & Processes Standard” by the end of 2011. The comprehensive standard will provide comparative data to allow anyone to evaluate the relative environmental performance of chemical products and their manufacturing technologies. The next step could be an information label, similar to nutrition information labels now used on foods, that manufacturers can apply to product packaging to describe the product’s eco-friendly attributes making it easier to choose “greener” products.

Mercury levels are increasing in popular species of game fish in Lake Erie
Environmental Science & Technology

Satyendra Bhavsar and colleagues are reporting that mercury levels in popular species of game fish in Lake Erie have increased. The researchers found that mercury levels in the fish steadily declined from the mid-1970s to 2007 in the upper Great Lakes (Superior and Huron). In recent years (between 1990 and 2007), however, the mercury concentrations leveled-off in Lake Ontario walleye but appear to be increasing in Lake Erie walleye. The mercury increases in Lake Erie walleye are likely caused by a combination of factors, including modifications in Lake Erie’s foodweb due to invasions of dreissenid mussels and round goby, the scientists suggest. The Great Lakes, the largest group of freshwater lakes in the world, are of significant economic importance to the United States and Canada due to the area’s $7 billion fishing industry. High levels of mercury in fish can potentially cause adverse health effects in people. Although government regulations and improved emissions control technologies have greatly reduced mercury emissions in the environment, their impact on mercury levels in Great Lakes fish is unclear.

Clean-up tools may help protect wetlands from Gulf of Mexico oil spill
Chemical & Engineering News

C&EN Assistant Editor Michael Torrice notes that scientists and engineers are using three basic tools to try to clean up the Gulf of Mexico spill, in which millions of gallons of oil escaped into the ocean from an oil rig following a pipe rupture. Those tools include mopping-up the oil with absorbent pads called “skimmers,” burning the oil in a controlled fashion, and breaking-up the oil into smaller particles using chemicals called dispersants. Despite these efforts, massive amounts of oil remain. But scientists are also investigating new clean-up methods. One involves applying dispersants under water to prevent the oil from rising to the surface and forming emulsions, reddish-brown clumps of an oil and water mixture that are extremely difficult to clean up. When oil hits the shore, scientists might rely on a more standard method and spray the wetlands with fertilizers that can boost the growth of naturally-occurring, oil-chomping bacteria that are found in the area. Whether or not this multipronged clean-up approach will save the wetlands remains to be seen.

Oil dispersants used in Gulf of Mexico unlikely to be endocrine disrupters and have relatively low toxicity to cells
Environmental Science & Technology

Richard Judson and colleagues report that eight of the most commonly used oil dispersants used to fight oil spills, such as the massive episode in the Gulf of Mexico, appear unlikely to act as endocrine disrupters – hormone-like substances that can interfere with reproduction, development, and other biological processes. More than 1.5 million gallons of dispersants have been used so far in the Deepwater Horizon spill. The tested dispersants also had a relatively low potential for cytotoxicity (cell death), with JD-2000 and SAF-RON GOLD showing the least potential. Scientists are concerned that some dispersants contain ingredients that turn into endocrine disrupters in the environment, and could harm marine mammals, fish, and humans. This is only results from the first round of EPA dispersant testing, but with an urgent need for such information in the Deepwater Horizon spill, the scientists applied a rapid screening method using mammalian cells to determine the eight dispersants’ potential to act as endocrine disrupters and relative toxicity to living cells. These are only results from the first round of EPA dispersant testing, however, they note that “there are other routes by which chemicals can cause endocrine disruption, as well as other types of toxicity that have not been tested for here.”

Homes of the poor and the affluent both have high levels of endocrine disruptors
Environmental Science & Technology

Ruthann Rudel and colleagues report that homes in low-income and affluent communities in California both had similarly high levels of endocrine disruptors, and the levels were higher in indoor air than outdoor air, according to a new study believed to be the first that paired indoor and outdoor air samples for such a wide range (104) of these substances. They note concern about the reproductive and other health effects of endocrine disrupting compounds (EDCs), which are found in many products used in the home. Examples include phthalates, which are found in older paints, electrical equipment, and building materials. EDCs also are among the ingredients in some pesticides, fragrances, and other materials. The scientists analyzed indoor and outdoor air samples as well as house dust from 40 homes in Richmond, Calif., an urban, industrial, low-income area, and 10 homes in Bolinas, Calif., an affluent, coastal community for the presence of 104 compounds, including 70 suspected EDCs. Levels were generally higher indoors than outdoors – 32 of the compounds occurred in higher concentrations indoors and only 2 were higher outdoors.

Travelling by car increases global temperatures more than travelling by plane, but only in the long term
Environmental Science & Technology

Driving a car increases global temperatures in the long run more than making the same long-distance journey by air according to a new study. However, in the short run travelling by air has a larger adverse climate impact because airplanes strongly affect short-lived warming processes at high altitudes. In the study, Jens Borken-Kleefeld and colleagues used, for the first time, a suite of climate chemistry models to consider the climate effects of all long- and short-lived gases, aerosols and cloud effects, not just carbon dioxide, resulting from transport worldwide. They concluded that in the long run the global temperature increase from a car trip will be on average higher than from a plane journey of the same distance. However, in the first years after the journey, air travel increases global temperatures four times more than car travel. Passenger trains and buses cause four to five times less impact than automobile travel for every mile a passenger travels. The findings prove robust despite the scientific uncertainties in understanding the earth’s climate system.

New plastic-like materials may say “shhhh!” to hush disease-causing microbes
Biomacromolecules

Elena Piletska and colleagues are reporting success in a first attempt to silence the chemical signals bacteria use to launch infection. They describe use of specially designed plastic-like materials, similar to those dentists use to repair damaged teeth, to capture signaling molecules in laboratory experiments and thwart microbes’ attempts to start an infection. The increase in antibiotic resistant bacteria has led to a global scientific quest for new antibiotics, and totally new approaches for dealing with bacteria that have caused millions of deaths throughout human history. The developed materials also reduce the ability of the bacteria to form biofilms. Bacteria form these slimy layers inside medical tubing, water supply pipes, and other surfaces and use them as a refuge to grow and multiply.

Schizophrenia drugs raise the volume of a key signaling system in the brain
ACS Chemical Neuroscience

Eric J. Aamodt and colleagues report the first example of a specific molecular effect produced by all antipsychotic drugs in any biological system. Scientists know little about how antipsychotic drugs work, aside from the drugs’ effects on one signaling chemical called dopamine. But studies suggest that medications like olanzapine, quetiapine, and clozapine affect other signaling systems in the brain such as the Akt signaling pathway, which influences behavior by regulating communication between brain cells. Scientists tested 13 antipsychotic drugs on a genetically modified form of the worm, C. elegans, which were wired to glow green to show activity of Akt, a signal that is too quiet in schizophrenic brains. They found that all of the drugs tested, representative of all major categories of antipsychotic medications, helped the worms maintain their characteristic green glow. The results highlight the importance of Akt signaling in schizophrenia, suggesting that medications or other approaches that increase Akt signaling might help to alleviate the symptoms of schizophrenia.

Nanotech breath sensor detects diabetes and potentially serious complication
Analytical Chemistry

Professor Sotiris E. Pratsinis and colleagues are reporting development and successful testing of a sensor that can instantly tell whether someone has Type I diabetes. Type I diabetics release unusually high levels of acetone when they exhale. The sensor could also be used by emergency room doctors to determine whether a patient has developed diabetic ketoacidosis, a potentially serious complication that happens when diabetics do not take enough insulin. If they have diabetic ketoacidosis, a dangerous buildup of acetone in the blood, they exhale even-larger amounts of acetone. Pratsinis’ team built an extremely sensitive acetone detector by directly depositing from a flame plume a thin film of semiconducting, mixed ceramic nanoparticles between a set of gold electrodes. The device acts like an electrical resistor — when it gets hit with a puff of acetone-filled air, its resistance drops, allowing more electricity to pass between the electrodes. If a diabetic were to breathe on the sensor, its resistance would suddenly drop indicating high levels of acetone.

Nicer than needles: Insulin pills for diabetes finally in clinical trials
Chemical & Engineering News

C&EN Senior Correspondent Ann Thayer reports that insulin pills to manage diabetes are finally moving ahead in clinical trials and a step-closer to the medicine cabinet. Drug manufacturers have tried for years to develop oral insulin without much success. Insulin is a peptide hormone that people with diabetes currently take by injection to bring their blood sugar to within normal levels, but the discomfort and inconvenience can make patients reluctant to use the drug frequently enough to adequately control their blood sugar. An oral form of insulin could help solve this problem, but stomach acids and enzymes easily destroy insulin and other protein-based drugs. Scientists have responded to this challenge by developing special coatings for insulin pills that prevent stomach acid from destroying them, and using additives that make it easier for the intestine to absorb large molecules like insulin. Only time will tell, however, whether these much-anticipated pills will make it to the market.

First paper “dipstick” test for determining blood type
Analytical Chemistry

Gil Garnier and colleagues are reporting development of the first “dipstick” test for instantly determining a person’s blood type at a cost of just a few pennies. Current methods for determining blood type require the use of sophisticated instruments that are not available in many poor parts of the world. But this test involves placing a drop of blood on a paper strip impregnated with antibodies to the antigens on red blood cells that determine blood type; the strip changes color to indicate blood type. The authors say it could be a boon to health care in developing countries, allowing for successful blood transfusions, and for use in veterinary medicine, typing animals’ blood in the field.

Eyes of cattle may become new windows to detect Mad Cow Disease
Analytical Chemistry

Jacob Petrich and colleagues report evidence that retinas of sheep infected with scrapie, a disease similar to Mad Cow Disease, emit a characteristic glow when examined with a beam of light from a special instrument. That test could help prevent the disease from spreading in the food supply. Past studies had suggested that chemical changes in an animal’s retina, the light sensitive nerve tissue in the back of the eye, may provide a basis for detecting prion diseases. They suggest that eye tests based on the finding could become important in the future for fast, inexpensive diagnosis of prion diseases and other neurological diseases such as Mad Cow Disease.

Small particles show big promise in beating unpleasant odors
Langmuir

Brij Moudgil and colleagues report development of a new approach for dealing with offensive household and other odors – one that doesn’t simply mask odors like today’s room fresheners, but eliminates them at the source. The scientists describe development of a new material consisting of nanoparticles of silica (the main ingredient in beach sand) – each 1/50,000th the width of a human hair – coated with copper. That metal has well-established antibacterial and anti-odor properties, and the nanoparticles gave copper a greater surface area to exert its effects. Tests of the particles against ethyl mercaptan, the stuff that gives natural gas its unpleasant odor, showed that nanoparticles were up to twice as effective as the gold standard – activated carbon – at removing the material’s foul-smelling odor. In addition to fighting odors, the particles also show promise for removing sulfur contaminants found in crude oil and for fighting harmful bacteria, they add.